• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.4
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• pp.328-341
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• 2017

In the control actuator system of a launch vehicle based on thrust vectoring, the interaction between electro-mechanical position servo and inertial load are combined with the dynamic characteristics of the flexible vehicle support to generate synthetic resonance. This occurred resonance is fed back to the attitude control system and can influence stability of launch vehicle. In this study, we proposed a simulation model to analyze synthetic resonance of electro-mechanical actuation system for thrust vector control and explained the results of simulation and test using dynamic force feedback control which improves dynamic characteristics of servo actuation system by reducing synthetic resonance.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.11
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• pp.2499-2504
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• 2013

Applications of dynamic position control are especially focused on cancellation of unknown disturbance against nonlinear dynamic plants. Control performance is technically dependent upon observation methodology of such disturbance signals. This paper presents a novel control strategy by using linear actuators based on CAN communication networks. Disturbance is measured from placing a ball on a flat plant and image processing technique is applied to observe dynamic position of a ball system. We devise a neural network based PI control system to realize robust control of the dynamic system.

• Journal of Industrial Convergence
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• v.18 no.2
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• pp.27-35
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• 2020

The purpose of this study was to investigate the effect of cervical and thoracic joint mobilization on cervical pain, cervical range of motion(ROM) and balance in adults with forward neck posture. A total 26 subjects were divided into a cervical joint mobilization group(CMG, n=13) and a thoracic joint mobilization group(TMG, n=13). performed joint mobilization three times per week for four weeks. As for changes in pain and ROM, statistically significant decrease were founded within group comparison(p<.05). In changes of static balance within group comparison, the CMG showed statically significant improvement in right foot on eyes closed(p<.05), while there were no significant changes in the TMG(p<.05). There were no significant differences were observed between group comparison(p<.05). In changes of dynamic balance within group comparison, the CMG and TMG were showed statistically significant improvement(p<.05). In conclusion, the joint mobilization on cervical and thoracic were effective on improving cervical pain, cervical range of motion and balance in adults with forward neck posture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.371-378
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• 2021

This study examined the effects of combined exercise training for preventing falls on the physical performance, falling index, and balance in elderly women. All subjects (N = 32) were recruited and divided randomly to either a combined exercise group (n= 16, EX) or non-exercise control group (n = 16, CON). During 12 weeks of training, the subjects in the EX performed the combined exercise programs (three times/week, 60min/session), and the subjects in the CON maintained their ordinary lives. At the PRE, MID, POST tests, All subjects completed senior fitness tests(dynamic balance, two minutes walking, sit and stand for 30 seconds), tests for falling risk with Tetrax, and tests for posture balance with the spine balance 3D. After the baseline tests, two-way repeated-measures ANOVA with contrast testing was used with SPSS 21.0. Alpha was set to 0.05. In the results, the dynamin balance (p=.001), two minutes walking (p=.001), sit and stand for 30 seconds (p=.001), falling risk (p=.002), and posture balance (p=.034) in the EX were significantly different, but not in the CON. Thus, elderly females who performed combined exercise training for 12 weeks can increase their physical fitness & posture stability and reduce their falling risk.

• Journal of the Korea Society of Computer and Information
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• v.25 no.8
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• pp.145-150
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• 2020

Forward head posture is one of the most recognized types of poor head and neck alignment. Poor head and neck alignment posture is a major contributor to compromised balance and neck pain, due to abnormal joint position sense and proprioception. Kinesio taping is an intervention method used clinically for the management of pain. Kinesio taping may produce its effects through pain reduction, stimulation of blood circulation, induction of muscle relaxation which provides correction of joint position, and providing stability to the muscles and joints without limiting the range of motion. Many studies have proved that kinesio taping has positive effects on the reduction of pain and improves alignment, on the other hand, some studies have not found. Kinesio taping may provide immediate pain relief and improved alignment following the application, but there is insufficient evidence to support sustained relief beyond that time and they recommended future studies to examine the benefits of kinesio taping as this would have a greater value in clinical practice. Therefore, this study is to investigate the effects of kinesio taping on the alignment of head posture and dynamic balance ability in people with forward head posture.

• Journal of the Korean Geophysical Society
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• v.9 no.2
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• pp.77-86
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• 2006

Aplications of the real-time kinematic GPS surveying and inertial measurement unit have been beingRTK GPS allows the use of a static base station and remote rover unit to allow for data collectionwithin several seconds and in real time. It is useful for monitoring the behaviors of massive structureslike bridges. And this study purposed to implement a method of deciding the acurate dynaimc attitudeof structures by IMU. In this study, among GPS methods, we used RTK GPS to analyze the precisionof monitoring and then on the basis of it, we developed a monitoring system using RTK GPS anda deviation betwen observation values, X axis was 1mm, Y axis was 1mm and Z axis 2.2mm. I tturned out that it was possible to monitor and measure structures by RTK GPS and IMU.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.41 no.4
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• pp.39-43
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• 2004

A typical theme of active vision systems is gaze-fixing of a camera. Here gaze-fixing of a camera means by steering orientation of a camera so that a given point on the object is always at the center of the image. For this we need to combine a function to analyze image data and a function to control orientation of a camera. This paper presents an algorithm for gaze-fixing of a camera where image analysis and orientation control are designed in a frame. At this time, for avoiding difficulties in implementing and aiming for real-time applications we design the algorithm to be a simple closed-form without using my information related to calibration of the camera or structure estimation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.180-185
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• 2009

Actuator-induced disturbance is one of the crucial factors of spacecraft attitude pointing and stability in fine attitude control problems. The control moment gyros (CMGs) are known as very attractive actuators from the point of high power and low weight. In order to develop a CMG as an actuator for fine controls, CMG-induced disturbances should be analyzed. Therefore, this paper aims to develop an analytic model and predict the effect of disturbances of CMGs by assuming static and dynamic imbalances. The proposed model is induced by the Lagrangian method on the basis of the small signal assumption. In this research, mechanical system of the CMG is designed and the main components of CMG are producted.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.2
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• pp.397-402
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• 1999

In this paper, we derive dynamic equation of a simulated helicopter and propose the control method base on a neural network to control its attitude. The coupling coefficients are adjusted to minimize the error between the output of a control system and the reference value. The gain of the proposed controller are automatically adjusted by the back propagation of a neural network. Simulation results using MATLAB are given in this paper.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.597-604
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• 2017

This study examined the effects of vestibular stimulation training on the static and dynamic balance of patients with chronic stroke. This study was conducted from July 15th to September 6th, 2014 and 20 subjects diagnosed with stroke participated in this study. The subjects were divided randomly into Group I (general therapeutic exercise, n=10) and Group II (vestibular stimulation training, n=10). Both groups were trained for 40 minutes, 3 times a week, for 6 weeks. The balance ability, static balance and dynamic balance, were evaluated using a Good Balance System and compared before-and-after intervention. In the vestibular training group, there were statistically significant differences in the left-right and anterior-posterior balance with the eyes closed and standing posture, in the left-right and anterior-posterior balance with the eyes open and standing posture, and moving time and distance. In the general therapeutic exercise group, there was no significant difference except in the left-right balance with the eyes open and standing posture. In conclusion, vestibular stimulation training had positive effects on the static and dynamic balance of chronic stroke patients, and this training can be effective in a treatment program to improve the balance ability of stroke patients.